/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2011 INRIA, France Telecom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.objectweb.asm.util;

import org.objectweb.asm.AnnotationVisitor;
import org.objectweb.asm.Attribute;
import org.objectweb.asm.FieldVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.TypePath;
import org.objectweb.asm.TypeReference;

/**
 * A {@link FieldVisitor} that checks that its methods are properly used.
 */
public class CheckFieldAdapter extends FieldVisitor {

  private boolean end;

  /**
   * Constructs a new {@link CheckFieldAdapter}. <i>Subclasses must not use this
   * constructor</i>. Instead, they must use the
   * {@link #CheckFieldAdapter(int, FieldVisitor)} version.
   * 
   * @param fv
   *          the field visitor to which this adapter must delegate calls.
   * @throws IllegalStateException
   *           If a subclass calls this constructor.
   */
  public CheckFieldAdapter(final FieldVisitor fv) {
    this(Opcodes.ASM6, fv);
    if (getClass() != CheckFieldAdapter.class) {
      throw new IllegalStateException();
    }
  }

  /**
   * Constructs a new {@link CheckFieldAdapter}.
   * 
   * @param api
   *          the ASM API version implemented by this visitor. Must be one of
   *          {@link Opcodes#ASM4}, {@link Opcodes#ASM5} or {@link Opcodes#ASM6}
   *          .
   * @param fv
   *          the field visitor to which this adapter must delegate calls.
   */
  protected CheckFieldAdapter(final int api, final FieldVisitor fv) {
    super(api, fv);
  }

  @Override
  public AnnotationVisitor visitAnnotation(final String desc, final boolean visible) {
    checkEnd();
    CheckMethodAdapter.checkDesc(desc, false);
    return new CheckAnnotationAdapter(super.visitAnnotation(desc, visible));
  }

  @Override
  public AnnotationVisitor visitTypeAnnotation(final int typeRef, final TypePath typePath, final String desc, final boolean visible) {
    checkEnd();
    int sort = typeRef >>> 24;
    if (sort != TypeReference.FIELD) {
      throw new IllegalArgumentException("Invalid type reference sort 0x" + Integer.toHexString(sort));
    }
    CheckClassAdapter.checkTypeRefAndPath(typeRef, typePath);
    CheckMethodAdapter.checkDesc(desc, false);
    return new CheckAnnotationAdapter(super.visitTypeAnnotation(typeRef, typePath, desc, visible));
  }

  @Override
  public void visitAttribute(final Attribute attr) {
    checkEnd();
    if (attr == null) {
      throw new IllegalArgumentException("Invalid attribute (must not be null)");
    }
    super.visitAttribute(attr);
  }

  @Override
  public void visitEnd() {
    checkEnd();
    end = true;
    super.visitEnd();
  }

  private void checkEnd() {
    if (end) {
      throw new IllegalStateException("Cannot call a visit method after visitEnd has been called");
    }
  }
}
